What is presbyopia?
Presbyopia is the gradual loss of the eyes’ ability to focus on close objects. It is a normal condition and usually the troublesome part of getting old. Presbyopia is usually noticed after the age of 40, and it continues to worsen until about the age of 65. A regular eye exam can confirm whether you have presbyopia. This condition can be fixed by wearing glasses or contact lenses. You may also consider surgery.
What are the symptoms of presbyopia?
Presbyopia appears gradually. After age 40, you may first notice these signs and symptoms:
- The tendency to hold reading materials further away to make letters clearer
- Blurred vision at the normal reading distance
- Eye strain or headache after reading or doing close work
What are the causes of presbyopia?
Your eyes rely on the cornea and lens to focus the reflected light on objects to create an image. The closer the object, the greater the curvature of the lens.
Both the cornea and lens refract the light entering the eye to focus the image on the retina, located in the inner back wall of the eye.
Unlike the cornea, the lens is somewhat elastic and can change its shape with the help of a circular muscle surrounding it. When you look at distant object, the circular muscle relaxes. When you look at a close object, the muscle contracts, allowing the flexible lens to curve and alter the strength of focus.
Presbyopia is caused by the hardening of the lens of the eye, which occurs with aging. As the lens becomes more rigid and less flexible, it cannot change shape to focus on close-up images. As a result, these images cannot be focused.
What are the risk factors of presbyopia?
- Age. Age is the most prominent risk factor for developing presbyopia. Almost everyone suffers from presbyopia after the age of 40.
- Other medical conditions. Being farsighted or having other certain diseases, such as diabetes, multiple sclerosis, or cardiovascular disease, can increase the risk of premature presbyopia that affects people under 40.
- Medications. Some medications are associated with premature presbyopia symptoms, and these include antidepressants, antihistamines, and diuretics.
How to diagnose presbyopia?
Presbyopia is diagnosed by performing a basic eye exam, which includes assessing refraction function and an eye health exam.
The refractive assessment determines if you have nearsightedness, farsightedness, astigmatism, or presbyopia. Your ophthalmologist may ask you to look through several lenses to test your vision at distance and near vision.
How to treat presbyopia?
The goal of treatment is to compensate for the inability of the eyes to focus on close objects. Treatment options include wearing corrective eyeglasses or contact lenses or undergoing refractive surgery.
Eyeglasses are a simple and safe option for correcting vision problems caused by presbyopia. You can use non-prescription reading glasses if you had good, uncorrected vision before developing presbyopia. Ask your ophthalmologist if non-prescription eyeglasses are right for you.
- Contact lenses
People who do not like to wear eyeglasses often use contact lenses to improve the vision problems caused by presbyopia. This option may not work in the case of specific conditions related to the eyelids, or tear ducts, or the surface of the eye, such as dry eyes.
- Eye refractive surgery
Eye refractive surgery changes the shape of your cornea. To treat presbyopia, this treatment can be used to improve close-up vision in the weak eye. It is as if you were wearing monovision lenses. Even after surgery, you may need to wear glasses for close-up work.
Talk to your ophthalmologist about possible side effects, as this procedure is irreversible. You may want to try monovision lenses for a short time before going for surgery.
The refractive surgery procedure includes:
- Conductive keratoplasty. This surgery uses radiofrequency to heat small spots around the cornea. The generated heat causes the edge of the cornea to shrink slightly, increasing its curvature and its ability to focus. The results of conductive keratoplasty vary from person to person and may not be permanent.
- Laser-assisted in situ keratomileusis (LASIK). In this procedure, your eye surgeon makes a thin flap suspended deep into your cornea. Then they use a laser to remove the inner layers of your cornea, to improve its domed shape. Recovering from LASIK surgery is usually faster and less painful than other corneal surgeries.
- Laser-assisted subepithelial keratectomy (LASEK). The surgeon creates an extremely thin flap in the outer cover of the cornea (the tissue lining the cornea). Then they use a laser to modify the shape of the outer layers of the cornea, steeping its curve and then returning the lining tissue to its place.
Photorefractive keratectomy (PRK). This procedure is very similar to LASEK, except that the surgeon completely removes the tissue lining the cornea, then uses the laser to reshape the cornea. The lining of the cornea is not repositioned, but it will grow back naturally, conforming to the shape of your new cornea.